About the genus
Erected by George Engelmann in 1848, the name Echinocereus derives from the Latin ‘echinus’ and ‘cereus’, meaning hedgehog and candle respectively.
Echinocerei come from as far north as South Dakota in the USA down to Oaxaca in southern Mexico. Some species live at sea-level and have been found on beaches while others embrace high altitudes, often being covered in snow during winter. Most species form clumps that vary in size from two stems to more than a hundred. The typical stem shape is short-cylindrical but some are distinctly cereoid while others can produce very thin, long growths that scramble through bushes for support.
Flowers are produced any time between early March and late September depending on the species. Almost invariably large, they are produced in a wide range of colours. Spines may be straight, short or long and wonderfully contorted but pectinate forms, which can be comfortably cradled in the hand, are also common.
How to grow them
While some echinocerei can prove rather challenging, success at growing these can vary from grower to grower. Discussing growing techniques produces a wide range that are successful. Current UK methods focus on good drainage with a base of John Innes and horticultural grit with 2–3mm pumice (or similar) being a useful addition to enhance drainage.
Seeds can be sown on almost pure chick grit, which is an inert, fine, flint grit. For good germination a temperature of around 30°C should be maintained with the pots enclosed in plastic bags. Grow lights are also helpful. When spines are detected on the seedlings open the bags and remove them after a few days. Keep the grit moist and feed weekly with a dilute solution of fertiliser.
Seedlings can be potted on in the following spring. Water used for seeds and seedlings should be clean, and if rainwater is used then this needs to be boiled to remove algal spores which may otherwise start to cover the surface of the grit.
When plants start to flower will depend on the species. Some will flower in their second year of growth while it may take others up to 20 years. It is usually the smaller species that produce flowers first. To encourage flowering the plants should be kept as cool as possible during winter. For cold-hardy species a few hard frosts help the development of flowers, coupled with holding back on the first watering of the season until buds are reasonably advanced. Some species, such as E. papillosus, will not tolerate any frost.
E. knippelianus: small-growing in nature with a tuberous root; this typically produces pink flowers from the base of the stem.
E. klapperi: Sonoran, red-flowering, clumping and easy to grow, flower and set seed.
E. triglochidiatus subsp. mojavensis: clumping, with pale-throated red flowers and twisting spines.
E. grandis: a columnar plant from islands off the east coast of Baja California producing white or pink flowers from the apex in maturity. E. maritimus: a shy, yellow flowering, clumping plant from the northern hills of Baja California.
Text and photos: Peter Berresford
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